Method and apparatus for casing vinyl film continuously



Nov. 15, 1955 W. D. HEDGES ET AL Original Filed Nov. 5, 1951 FIG-l 3Sheets-Sheet l TEXTIL BELT Fl 6-2 SYNTHETIC RUBBER COAT RUBBER'ZED /8 0RFI I /2 BELT WITH COATING SYNTHETIC RUBBER IN PLASTIC STATE 40 COATEDBELT COAT wITH APPLY TEXTILE POLYvINYL ACETATE SHEET TO PLASTIC /9 ORALKYD RESIN ON SURFACE CURED OR UNCURE'D /3 SYNTHETIC RUBBER COATINGHEAT COMBINED ELT, PLASTIC COATING AND DRY /4 TEXTILE SHEET POLYvINYL /5CO OL 42 ALCOHOL COAT STRIP PLASTIC A3 HEAT FUSED AND COAT WITHVULCANIZED RUBBER/6 gay- FROM l4 WITH COATING PRINT MULTIPLE COATSPOLYVINYL ALCOHOL AFTER PREVIOUS COATS DRY INvENTORs JOHN C. LOWMANWILLIAM D.HEDGE$ BY 77.2.4 I K ATTORNEYS Nbv- 55 w. D. HEDGES ET AL2,723,962

METHOD AND APPARATUS FOR CASING VINYL FILM CONTINUOUSLY Original FiledNov. 5, 1951 3 Sheets-Sheet 2 INVENTORS JOHN c. LOWMAN WILLIAM D. HEDGESBYML m ATTORNEYS Nov. 15, 1955 w. D. HEDGES ET AL 2,723,962

METHOD AND APPARATUS FOR CASING VINYL FILM CONTI'NUOUSLY Original FiledNOV. 5, 1951 3 Sheets-Sheet 3 INVENTORS JOHN C. LOWMAN WILLIAM D. HEDGESm a 77:1; ATTORNEYS 2,723,2 METHOD AND APPARATUS FOR CASING vinyl.

FILM; CDNTINUOiiSliY 11 William D. Hedges and John C Zowman, FranklinCounty, one, assignors to Columbus Coated Fabr cs Corporation,Colurnbngflhio, a eos'po rat ion of fi hio Original application November5, 1951,. Serial No.

254,926;-iiow Patent No2,704,735,dated March 22, 1 255.; Divided andthis application July 1, 1952 Serial Qm- 9-7i 4 ot gm. on. 260 22) Thisinvention relates to resinous compositions and is a "divisi'or'fof ourcfo pending application, Serial No. 254,926, filed Novembefs, 1951 endassigned to Columbus Coated Fabrics Corpotationfian Ohio corporation,56fColumbus;Ohio. he? eoating compositions with which? this invention iscdncernedar e particularly resinous "compositionsfor the "casting: ofresinousfilms either to f textile material. tofote, in the particularart with which this inven- "concerned, great difficulty has beenexperienced panama; ej cebfnie present invention, therefore, is

"the provision of a resinous eomposition particularly her in a supported or unsupported state.

a further object to p rov ide a composition for the fi m ceating, thatwill be non-adherent or slightly nona'dherentto the supported resin.

It is an object to provide a composition of the resin itself of suchcharacter, that it can be applied in a liquid oryiscousstate and can becaused to' adhere to atextile support and after so adhering can bestripped from its supporting belt, and thereafter fused. i

It is an object to provide a composition of a resin for such coatingpurposes whichca'n be cast on the belty'be strippfld from the belt,which willnotadhere to the belt,

but which will adhere to a carner for removing it from 1 the belt, suchas'a textile carrier andthe like.

It is ariobject' to provide such a 'coating' in a paste orsuspension-form so that it can be cast, spread rolledpr otherwise coatedupon the surface of the belt. Referring 'to the drawings:

Figure 1 is a flow sheet showing the steps in the process ofpreparingthe surface ofa belt or carrier for receiving "a"film of thematerial of my invention, bycoating with synthetic'rubber'or modifiedsynthetic rubber; L p

Figurelis a fiow sheet illustrating the steps in applythe resin ceatingto the belt, in treatingeit while on l the belt, and removing it fromthe belt. 'LFigure 3 is a diagrammatic flow sheet illustratingthemechanism in diagrammatic form for the coating'of the belt, thevulcanization of the coating, the top coating of the belt, the coatingof the belt with resin, and the application of a textile carrier to theresin coating on the belt and its removal with the resin coating. Figure4 is a top plan isometric view showing in perspective the end of thetreatment apparatus on which the vinyl paste is applied and to whichthetextilesheet is applied for stripping. Figure 5 is asection on theline 5-5 looking in the direction of the arrows on Figure 3. l

Figure 6 is a section on the line 66 looking in the direction of thearrows on Figure 3. a I

v Figure '1 is a section onithe line 7 10f. Figure 3. l oking in thedirectionof thearrows.

Figure 8 is 'a section on. the line 8 8 .ofMFigure. 3

H looking in the direction of the arrows.

, looking in the direction of the arrows;

Figure 11 is a section'on' the. line ,1111 10 is to be coatedwith rubbering the v is in paste form the textile sheet lil'lCl'lbVj/ lfth it bythe roller .10..,.,The composite structure Figure 9 is a section on theline 9 9 ,of,Figure. 3 looking in the directionof the arrows. 1

Figure 10 is a section on the line 10 10 of. Figure 4 looking in thedirection of the arrows on Figure 4.

Referring to the figures, his a textilematerial .which or syntheticrubber .coating 2 and on top of this coating has been placed thepolyvinyl coating 3. Then the belt is dried at 4 and additionalpolyvinyl coatings have been applied at 5. Thence the rubber coated beltis vulcanized ,at 6 and. thenpa'ss'es nnder additional polyvinyl.alcohol sprays 7. LThenjthe composite belt proceeds beneath theapplicator. 8 which may use spray, spreader, roller coater or the.like,for"the application for the vinyl paste designated 8a. l whilethis 9 isbrought into engageof the supporting belt, paste and textile sheet ispassed through the heater 11, and thence through the cooler 12 to thepoint Where the textile sheet 13, with the vinyl coating (which is newhard) is removed froinf'the belt carrier as'indicatjedbver the roller14. If desifed this sheet .13 can be heat :15.

fused at 400 F, see s'tep Thereafter, the sheet can be printed. 3Referring to the drawings, the following are the various steps and theprocesses of forming a carrier servicegapplyresin to the surface andremoving the resin from "the; surface.

.BE I ARRIE FQ M IIQN Any suitable textile material such as twill, duckor sheeting is utilized for the underlyingconveyor'or'belt. There isfirstcalendered or coated into the surface of this belt a rubber'coatingof butyl', GRS or other naturalof synthetic'rubber coating.

,The'sec'ond step is to coat rubberized surface with polyvinyl acetateplasticized with'a'n alkyd resin." There after, the coating is dried andanother co'at of polyvinyl alcohol is applied. The composition belt'isthen heat coating.

vthis paste. Resin paste is composed 'of the fused and vulcanized sothat the rubber and the coatings art b'oth fused together at atemperature of about 275 F. rubber or synthetic coating is After theheat fusing and vulcanization, multiple coats of polyvinyl alcohol maybe applied and then dried. The belt is now ready for the application ofits tempofa'ry resin coating for the casting and subsequent strippingofthat The belt is coated with a vinyl resin, preferably in'a liquidpaste form. That is, the belt is pliable and has a smooth base, willstand a temperature of from 350 to 4009*1F. with alternate cycling ofcooling and heatingtas set forth hereinafter, it forms a permanentsupport for following as set forth in the subsequent examples: Example Ii The following is afforinula used in a typical textile paste:

am A copolymer of vinyl acetate and vinyl chloridennlfl'ti 'A pigment,such as titanium dioxide T 3 A filler, such as claiy 4 Aplasticizer ofan a kyd type; 2 'Dioetytphthalate"; A secondary plasticizer such astetrahydrofurfuryl- 1 foleate ...2 A heat stabilizer such as dibasiclead stearate ...3

A releasing agent, such as paraflin', waX,'e't'c'. .1

. Naphtha 1 acid and having a molecular weight of about 6000. A

suitable plasticizing resin of this type is described in U. S. Patent2,071,215. Such a plasticizing alkyd resin of this character is marketedas Paraplex G40 by Rohm and Haas and is useful for imparting certainflow properties to the paste as well as definite desirable properties inthe finished fused' film. Thetetrahydrofurfuryloleate or fatty acid typeplasticizer is known as a secondary plasticizer and is 'used to impartproper film and drape in the film.

. The foregoing composition is mixed in one operation at .roomtemperature. 2 Example 11 Parts Vinyl vresin Pigment 3 v Filler 4Methylacetyl l'icinnleate 2 Dioctyl phthalate 4 Dibasic lead carbonate0.3 Paraffin 0.1

Example 111 Parts Vinyl resin (copolymer) 10 .Glyptal resin(glycerol-phthalic acid polymer) 3 Dioctyl phthalate 2 Dibasic leadstear 3 Parafiin 0.1 1.5

After one of the foregoing resinous coatings is applied in paste form tothe surface of the belt, it is preferred to apply a textile supportingsheet as illustrated in Figure 4, or otherwise, which is broughtin-contact with the surface of the paste and pressed into engagementwith the paste so that the paste impregnates and coats one side of thetextile materials. Thereafter, the combination of the supporting belt,the plastic coating and the textile sheet is. subjected to a temperatureof up to 400 F. Then the combined product of the belt, plastic coating,and textile sheet are cooled down to 150 F. or below. Thereafter, thetextile impregnated sheet is stripped from the belt and removes with itthe plastic coat. The textile treated sheet is then ready for fusing, ifnecessary, or suitable decorative printing, or both. The successivesteps are shown in Figure 2 and in Figure 4 of the drawings forming apart of this invention.

Optionally, the resinous coating can be heat treated and hardened priorto the application of the textile sheet, printed open and then reheatedin engagement with the textile sheet to impregnate the sheet with theprinted resinous film.

It will then be understood that in the normal method when the fabric isapplied to the vinyl coating, the latter is a paste with no strength. Inthis stage the textile material is pressed into the paste andthereafter, the subsequent steps of heating, chilling and stripping takeplace. It is also optionalto'heat the vinyl until it becomes sticky andadhesive and then to apply to the textile material.

It is important that the polyvinyl chloride, or a copolymer of polyvinylchloride and polyvinyl acetate, or a copolymer of polyvinyl chloride andvinylidene chloride be soproduced that the particle size of the resinswill wet out with the minimum of plasticizer or any other liquid so asto produce a paste or suspension of ingredients that can be cast,spread, or roller coated. It is my object to provide a resin surfacesuitable for preventing excessive absorption of the liquid phase of thepaste so that these liquids may be used as a carrying medium for theingredients of the composition.

, the pastes tacky surface.

After the resinous coating is removed by stripping the textile materialfrom the belt, the belt is available for subsequent similar treatmentsof a paste resin and stripping. It has been found that a belt of thisinvention provides a smooth surface thatresists scratching, that can beused a number of times and that is relatively cheap and flexible and canbe handled because of its minimum weight without difficulty. Theresinous coating is readily strippable from it without damage to thesupporting belt.

It is to be understood that there are a variety of ways of applyingthese coatings by doctor blade, roller coating, a spreading knife, sprayand the like. The belt is capable of repeated beatings to 350 to 400 F.to fuse the resin after it has been deposited upon the casting belt orsheet.

It will be further understood that there are various types of resinousproducts that may be made into a vinyl coating mixture known asorganosols, plastisols or paste dispersions. Our basic objective is toprovide a continuous film from this type of coating mixture. Nosatisfactory casting surface has been developed so far as I know, priorto the invention described herein. The initial cost of metal belts isvery high as they are usually made of stainless steel and they are alsosubject to the dilficulty of warping, twisting and rippling on theedgesrnaking it difficult to provide a smooth and uniform surface forcasting purposes. The alternate. changes in temperature further changethe expansion of the stainless steel belt which causes a physical changein the regularity of its daub, when applied to such a surface asdeveloped from the foregoing process and compounds and properly fusedwill not strip from a surface unless that surface is treated asheretofore described. We have found polyvinyl alcohol to be one of themost satisfactory surface treating It is these liquids that provideagents for stripping vinyl coating. Polyvinyl "alcohol, however, willnot, in itself, adhere to rubber surfaces.

We have found it, therefore, necessary to discover some combining agentby which the polyvinyl alcohol could be made to adhere to uncuredrubber. We have found that,.if a coatingconsisting of an emulsion ofpolyvinyl acetate and plasticized with an alkyd resin is first appliedto the uncured rubber coating and, after drying, a coat ofpolyvinylalcohol can be applied and then the treated fabric of the beltcan be fused. Fusing time and temperature depends, of course; on thetype of the synthetic rubber used as the base coating and upon thedesired hardness or stiffness of the coated fabric desired. After thematerial has thus been fused, additional coats of polyvinyl alcohol areapplied until the desired smoothness is obtained. This coated fabricbecomes a satisfactory casting surface and may be used a number of timesuntil marring of the surface takes place, but, in such an event, it isonly necessary'to refinish the casting surface of the coated fabric byadditional coats of polyvinyl alcohol. It will be understood that itmakes no difference whether the belt surface consists of a continuousbelt or a long piece.

It is our object to not only produce independent film by this procedurebut, also, produce fabric laminated to the film.

We produce both an unsupported cast film or a textile laminated castfilmby our process and by my belt.

It will be understood that we desire to comprehend within our inventionvarious adaptations and changes both mechanically and chemically whichmay benecessary to adapt it to varying conditions of use and types ofmaterials. These variations and changes it isdesired 5 to comprehendwithin the scope of our hereinafter ap- References Cited in the file ofthis patent 252 UNITED STATES PATENTS A textile sheet impregnated with aplastic composition g g 1g which consists in the following constituentparts by 5 2468165 :92: 2: g: 1949 Welght' Parts 2,528,507 Foye Nov. 7,1950 A copolymer of vinyl acetate and vinyl chloride 10 OTHER REFERENCESTitanium dioxide 3 b 7 N 5 A 1 5 5 Powdered clay 4 10 5 er Ag v01 6ugust 9 0, p g 5 A linear polyester of 1,2 propylene glycol and sebacicZimmerman et a1. Rubber Age VOL 63 Na 3, Decerm acid having a molecularWeight of about 6000---- 2 bar 1950 Pages Dioctyl phthalate 4Tetrahydrofurfuryloleate 0.2 Dibasic lead stearate 0.3 15

Parafiin wax 0.1

